JPH08167082A - Crimes prevention device for window - Google Patents

Abstract

PURPOSE: To catch vibration by a trespass action at low cost with good sensitivity by fitting a piezoelectric element to part of the external frame of a window, a sliding door, a showcase, etc., and detecting vibrations of all of the window glass, door plate, glass plate, etc., in the external frame at one place. CONSTITUTION: The piezoelectric element 1 fitted to part of the external frame generates a voltage output 1a corresponding to strain by vibration and its signal is amplified by an amplifying circuit part 2 to generate an amplified voltage 2a; and a filter circuit part 3 attenuates frequency components of various vibration noises to generate a voltage output 3a consisting principally of a detection object frequency component, e.g. 5kHz. Thus, this 5kHz component is extracted to prevent malfunction caused by vibration noises, and vibration generated by an entry into the window can be detected. Then the level of the voltage output 3a is compared with a threshold value voltage level and when the output 3a exceeds the threshold value voltage, an alarming operation signal 4a is outputted to make a buzzer sound.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a security device for detecting an intrusion into a house through a window, a sliding door or the like, or a vibration occurring when a showcase or the like is destroyed, and issuing an alarm.

[0002]

2. Description of the Related Art Conventionally, when a window glass is broken, a piezoelectric element is attached to the window glass to detect an AE (acoustic emission) that is ordered when the window glass is broken, and an alarm is issued when the window glass is broken. Alternatively, a device that detects the airborne propagation of ultrasonic waves generated when the window glass is destroyed with an ultrasonic microphone installed at a position away from the window and issues an alarm, or a sliding door, a magnet switch or the like on the window frame There is a device that attaches an on / off switch and issues an alarm when the switch is activated when a window is opened. Moreover, the AE generated when the glass of the showcase is broken is broken by the piezoelectric element attached to the glass of the showcase.
There is a device that detects an alarm and issues an alarm.

[0003]

However, in the conventional glass breakage detection system or the magnet switch system, it is necessary to attach a piezoelectric element to each window glass or attach a magnet switch to each window frame. There is a problem that the number of detection units increases. Also, in the method of detecting the airborne sound from the whole window with the ultrasonic microphone installed at one place, if you forget to lock the window, if it is opened and closed carefully without producing sound, There was a problem that it could not be detected.

The present invention has been made in view of the above circumstances, and provides an inexpensive and highly sensitive security device in which the number of detection units of the security device attached to a window, a sliding door, a showcase or the like is reduced.

[0005]

According to the present invention, a piezoelectric element mounted on a part of an outer frame such as a window, a sliding door, a showcase, etc., an amplifier circuit section, a filter circuit section, a threshold circuit section, an alarm circuit section, It is constituted by a power supply circuit unit, and detects vibrations of all windows, door plates, glass plates, and the like in the outer frame at one place.

[0006]

[Function] By attaching a piezoelectric element to a part of an outer frame supporting a window, a door plate, a glass plate, etc., all windows in the outer frame,
It is possible to detect with high sensitivity solid-borne vibrations caused by opening / closing, breakage, impact, and the like given to a door plate, a glass plate, and the like.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a window security device according to the present invention. In FIG. 1, a ferroelectric material such as zircon / lead titanate ceramics (PZT) or barium titanate ceramics (BT) is polarized. FIG. 2 shows an example of a piezoelectric element 1 which generates a voltage when strain is applied.
Various types such as a piezoelectric element simple type shown in FIG. 2A and a unimorph type shown in FIG. 2B are commercially available, and the hatched portion in FIG. 2 is adhered to an outer frame of a window described later.

Reference numeral 2 is an amplification circuit section for amplifying the voltage output 1a generated in the piezoelectric element 1, and 3 is amplified by the amplification circuit section 2, and frequency components of miscellaneous vibration noise are selected from the amplified voltage outputs 2a having various frequency components. Filter circuit section 4 for attenuating the voltage output 3a output from the filter circuit section 3
When a voltage higher than a certain threshold value among them is input, the threshold circuit section 5 which performs a switching operation and outputs a constant operating voltage 4a outputs an alarm buzzer by the operating voltage 4a of the threshold circuit section 4 ( Alarm circuit unit for ringing (not shown), 6
Is a power supply circuit unit for supplying the power required to operate the amplifier circuit unit 2, the filter circuit unit 3, the threshold value circuit unit 4, and the alarm circuit unit 5, and 7 is used when the security device for a window is used. It is a manual on / off switch that operates only.

FIG. 3 is a view showing a mounting place when the security device for a window is mounted on a window. In the figure, 8 is a window, 9 is a window glass, 10 is a window frame, 11 is a key, 12 is an outer frame, 13 is the outer frame 1
2 is a window security device of the present invention attached to a part of the window security device 2. FIG. 4 is an external view of the window security device 13, and reference numeral 14 denotes an alarm buzzer sounding hole.

Next, the operation of the window security device of the present invention will be described with reference to FIGS. 1 and 3. When considering the intrusion from the window 8, the intruder checks whether the key 11 is locked, and when the key 11 is not locked, opens the window 8 and enters. At this time, if opened in the direction of the arrow shown in FIG. 3, the lower roller 10a of the window frame 10 moves along the rail groove 12a of the outer frame 12, but at this time, the outer frame 12 generates a slight vibration. The vibration applied to the outer frame 12 propagates through the outer frame 12 and vibrates the piezoelectric element 1 accommodated in a part of the outer frame 12. The vibrated piezoelectric element 1 generates a voltage output 1a according to the distortion caused by the vibration. The voltage output 1a is amplified by the amplifier circuit section 2 and outputs an amplified voltage 2a. The amplified voltage 2a is attenuated by the filter circuit section 3 to attenuate the frequency components of the noise noise, and becomes a voltage output 3a mainly including the frequency component to be detected (for example, 5 kHz). FIG. 5 shows a frequency measurement example of the vibration to be detected and the coarse vibration noise. By extracting the 5 KHz component, a malfunction due to the coarse vibration noise can be prevented, and only the vibration due to the intrusion from the window can be detected.

Next, the voltage level of the voltage output 3a is compared with the threshold voltage level set in the threshold circuit section 4, and if the voltage output 3a exceeds the threshold voltage, the alarm operation signal 4a is output. The alarm circuit section 5 causes the alarm buzzer to ring. When the intruder opens the window 8 by the above operation, the alarm buzzer sounds and the intrusion can be prevented.

In the state where the key 11 of the window 8 is locked,
In the case where the window glass 9 is cut and intruded in the vicinity, when the window glass 9 is cut by a glass cutter or the like, the vibration is similarly propagated from the window glass 9 to the window frame 10 and the outer frame 12, and the alarm buzzer sounds. Can be done.

Not only the example of attaching the window to the outer frame described above, but even if it is attached to a part of the outer frame of the sliding door or the showcase, the vibration applied to the door plate and the glass plate can be detected with high sensitivity. As shown in FIG. 6, the security device for a window of the invention detects the vibration in the inner frame 15 such as a window, a sliding door, and a showcase by a piezoelectric element attached to a part of the outer frame 16 holding the inner frame 15. Anything is fine.

[0014]

As described above, the present invention relates to a window, a sliding door,
By attaching a piezoelectric element to a part of the outer frame of a showcase, etc., it can be realized as an inexpensive security device by detecting vibrations of all window glass, door plate, glass plate, etc. in the outer frame at one place. In addition, there is a great effect that the vibration caused by the intruding action can be captured with high sensitivity by detecting the vibration propagated through the solid.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a window crime prevention device of the present invention.

FIG. 2 is a view showing a piezoelectric element according to the present invention.

FIG. 3 is a view showing an attached state of the window security device of the present invention.

FIG. 4 is an external view of the window security device of the present invention.

FIG. 5 is a diagram showing frequencies of vibrations to be detected and noises of miscellaneous vibrations.

FIG. 6 is a diagram illustrating a mounting position of the window security device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Piezoelectric element 2 Amplification circuit part 3 Filter circuit part 4 Threshold circuit part 5 Alarm circuit part 6 Power supply circuit part 7 Manual on / off switch 8 Window 9 Window glass 10 Window frame 11 Key 12 Outer frame 13 Security device for windows

Claims (1)

[Claims] 1. A piezoelectric element attached to a part of an outer frame such as a window, a sliding door, a showcase, and the like, an amplifier circuit section, a filter circuit section, a threshold circuit section, an alarm circuit section, and a power supply circuit section. A security device for windows, wherein vibrations of all windows, door plates, glass plates, etc. in the outer frame are detected at one place.